Hybrid electric vehicle (HEVs) typically include an internal combustion engine (ICE) coupled with an electric machine or motor/generator (EM), and include various other components including ICE turbochargers. Such HEVs may further include turbocharger lag reduction systems that reduce the amount of time needed for turbochargers to attain operational speeds. Such lag reduction systems sometimes include pressure tanks that store compressed air, which can be discharged to quickly ramp up the speed of the turbochargers to improve vehicle performance. In the past, such pressure tanks have been recharged utilizing energy from the ICE, EM, and/or batteries. However, hybrid electric vehicles may require recharge of the pressure tank when the ICE is shutdown during electric only operations, and without consuming power from the EM and batteries.